Method of bueototgr comminuted fuel



J. H. COOPER.

METHOD 0F BURNING COMMKNUTED FUEL.

v APPLICATION FILED JULY 20,1918- A 1 ,$597,266.l Patented Nov. 15, 1921.

1. H. COOPER.

METHOD 0F BURNING COMMINUTED FUEL. V

APPLICATION FILED JULY 20! l9l8.

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APPLICATION FILED IuLY 20,19I8.

1,397,266. PatenteaNov.15,1921.

3 SHEETS-.SHEET 3.

UNITED STATES PATENT OFFICE.

JOSEPH H. COOPER, 0F CHICAGO, ILLINOIS.

METHOD 0F BURNING COMMINUTED FUEL.

To all whom t may concern.'

Be it known that I, JosnPI-r H. Coornr., a citizen of the United States, residing in Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Methods of Burning Comminuted Fuel, of which the following is a specication.

This invention relates to the burning of comminuted fuel and has for its primary object the provision of an improved methoc of burning said fuel Ywhereby the maximum heating efficiency is procured, whereby the lire-box or other fire containing chamber employed is protected from the gougingor blow torch effect of a flame confined in a narrow path and traveling at high velocity, whereby all volatile matter is gasified and all combustible matter burned within the lire-box, whereby all non-volatile and noncombustible matter is granulated within the fire-box, and whereby the fuel employed is with great thoroughness mixed with the air necessary `to support its combustion.

While the method of this inventionis adapted for the advantageous use ofliquid fuel, they are more particularly intended for the consumption of pulverized fuels such as coal-dust.

Other objects and advantages of the invention will appear from the following description, taken in conjunction with the accompanying drawings which form a part of y this specification and illustrate the preferred embodiment'of the invention- In the drawings:

Figure 1 is a vertical fragmentary section of a locomotive taken approximately on line 1-1 of Fig. 2.

Fig. 2 is a section taken approximately 'on line 2-2 of Fig. 1.

Fig. 3 is a section taken: on line 3-3 of Fig. 1 and looking toward the front of the locomotive. v

Fig. 4 is a section taken on line4-4 of Fig. 1 and looking toward the rear of the locomotive.

Supported in any suitable manner (not shown) from the driving wheels 10 and '11 and cab supporting trailer wheels V12 through Athe medium of a frame 13 are the locomotive fire-box and boiler illustrated in the drawings. The flame 'lines for the vboiler are shown at 14 projecting forwardly from the flue sheet 15 at the front end of the lirebox and within the boiler ,shell shown at Specification of Letters Patent.

Patented Nov. 15,1921.

1918. Serial No. 245,802. l

1G. The crown sheet of the fire-box is indi-v cated at 1'?, the bottom sheet at 18 and the back sheet at 19. The lower edges of the boiler shell 16 about'the fire-box are secured against the outer surface of the mud ring 2O as arer also the lower edges of the flue sheet 15, back sheet 19,*and side sheets 21 of the fire-box. Preferably the bottom vsheet 18 of the fire-box is considerably below the mud ring 2O and is connected thereto by up- 23. f The sheets 22 and 23 have their greatest vertical'extent and highest pitch atthe rear wardly and outwardly slanting sheets 22 and mud ring 20, one of the objects of the present invention being that the flame developed can be safely permitted to strike directly against the sheets of the lire-box which are in contactv on their opposite sides with the water and the steam in the boiler. The heat-V ing efficiency of the fuel burned is thereby increased inasmuch as there is no thick layer of fire brick interposed between the flame and the water contacting sheets nl: the firebox, and the heating of the water is facilitated; In'central position in the front wall of the fire-box and at the bottom thereof an aperture 28 for injection of fuel is formed, and a Tmixer casting 29 is bolted in any suitable manner to the mud ring 20 and bottom sheet 18 and has its horizontal mixing chamber `31 alined and in communication with aperture 28. Fuel feed pipe 32 conveys comminuted fuel suspended in air from the tender (not shown) along the exterior of thev tional air necessary is conveyed through hot air flues 34 formed by securing an angular strip of steel vhorizontally to the exterior of the slanting bottom walls 22 and 23, through an aperture 35 extending upwardly through the bottom wall of the mixing chamber 31 opposite aperture 33. Preferably theA forward wall of aperture 35 stands slightly forward of the forward wall of aperture 33. The rear endg of hot air flues 34 are each closed by a controlling door 36 hinged as at 37 to thebottom sheets 22 and 23 respectively. The remaining air additional for proper combustion is furnished cold tothe mixing chamber 31 from a rotary fan 40 and a cold air pipe 38 through a cold air injector 39 fitting the forward end of the casting 29 and having its rear face preferably flush with the forward wall of aperture'33 and positioned consequently above the center of aperture 35; the rear tip of the injector 39 is also spaced slightly above the bottom wall of mixing chamber 31 in order that the cold air from fan 40 may, on the injector principle,=draw hot air through flues 34 and aperture 35. In order that the cloud of fuel and air supplied through mixing chamber 31 may initially substantially lill the narrow bottom portion of the fire-box between the lower edges of sheets 22 and 23, themixingchamber is in cross section an elongated rectangle having its `greatest dimension horizontal, and the cold air feed'opening of injector 39 is similarly shaped and positioned in cross section, while at'the same time aperture 35 is' substantially cio-extensive from left to rightwith the width of the mixing chamber and the aperture 33 isrcentrally positioned in the top wall of the mixing vchamber but is considerably' shorter than aper-A botomof the mixing chamber 31 and has the normal tendency of hotJ air to rise; that the fuel laden air from pipe 32 i5 intro-auced into the top of the mixing chamber through an aperture shorter than that for the hot air, the fuel, being heavier than air, having a norn'ialA tendency to sink. rfhe streamsiof fuel laden air and hot air are so positioned rtherefore that 4advantage is taken of their physical characteristics. the oneto sink and the other to rise, in order that the best possible-"mixture of these two currents may result. The hot air ,intake aperture' being longer than that 'forthe-fuel, the hot air envelopes' the incoming fuel just asfthe two streams of air enter the mixing chamber.

1t will be 'also noted that the necessary 4cold air is fed into the mixing 'chamber between the opposite apertures 33 and 35, and at right angles tothe 4direction of the vliow of hot air and fuel entering the mixing chamber. The cold air from 'fan 40 is introduced at a comparatively low velocity in order to eliminate a blow torch effect of the flame upon the interior of the fire box, but its velocity is sufficient to draw hot air through fiues 34 and to violently agitate the mixture of hot air and fuel constantly formed at the forward end of the mixing chamber. rEhe draft offuel laden air through pipe 32 is purposely of low velocity, it being understood that the normal draft induced in every locomotive by reason of the exhaust from the cylinders (not shown) is present in the firebox. rIhe velocities with which the fuel laden air and the cold airv enter the mixing chamber may of course be varied by control of the draft through pipe 32 by any of the ordinary means (not shown) and by increasing or decreasing the speed of rotation of fan 40. These fluctuations will be made in`-accordance with the requirements of conditions, but the draft induced through the fire-box will at all times)` be sluggish and in accordance with the short llame principle of consumption of comminuted fuelV asV distinguished Vfrom the violent draft provided on the long flame combustion principle in such constructions as are employed in cement kilns and the like, where a narrow path of 'liame traveling at high velocity has a gouging blow torch effect upon any Substance against which it isl directed.

The present invention contemplates the production of a continuous but attenuated flame in the hre-box through which such a rela-tively sluggish draft passes as has just been mentioned. In order to give the flame a long path of travel through the lire-box,

the fuel is inject-ed only'at the forward endV of the fire-box in the present invention and passes from mixing chamber 31, Vthrough aperture 28 and along` the fire brick covering the bottom sheet 18, to the-rear wall of the fire-box. Here it is turned forwardly and upwardly by a baiiie "arch 41 of `fire brick traversing the rear portion box from side to side, slanting forwardly and upwardly a comparatively short dis tance therein, and spaced above the bottom of the hre-box a sufficient distance to permit the combustible mixture already kindled to steam feed pipe 44 thatenters the arch preferably through the back sheet 19v of the firebox. The effect of the steam sheet sprayed through aperture 42'is three-fold; it changes the direction ofthe iiame to one Ysubstantiallyhorizontal, gives added impetus to the flamel to project/it against the flue sheet of the fire Y against the side sheets 2l.

15, and also spreads the flame horizontally across the whole area ofthe fire-box and j Under the influence of this steam sheet the flame strikes the flue sheet l5 at a point indicated by numeral 45, being substantially horizontally opposite the forward edge of the baffle arch 4l. lt rom a position on the flue sheet just above the area indicated at 45, a smoke arch 4G, supported on the customary arch tubes 47, projects baclwardly and upwardly through the lire-box in order to deflect the flame backwardly` before permitting it to pass to the flues 14 the rear openings of all of which lie above the bottom of this arch 46. By introducing the flame at the forward end of the fire-box and the bottom thereof and deflecting it three times as shown by the arrows in Fig. l, I so increase its length as to allow time during its passage for the vaporization of all volatile matter, the complete burning of all combustible matter', and also the granulation ofthe large quantity of liquid slag formed from the flame and which heretofore has in most instances been projected in liquid form against the flue sheet and into the flues, necessitating very frequently the cleaning off of the slag thus plastered on the flues and flue sheet. A large portion of the granulated slag will drop to the bottom of the fire-box and be swept backwardly therein by the blast from the mixing chamber and will fall through aperture 26 into the slag hopper 24. The remaining portion will be blown as cinders through the flues 14 and projected from the stack in cases where this invention is applied to locomotives. Attention is drawn to the fact that the backward sweep of incoming fuel along the bottom of the lire-box constantly removes the granular slag formed. The attenuation of the flame, combined with the action of the steam sheet in spreading the llame throughout the lire-box and against the side sheets, greatly increases the area of contact between the dame and the side sheets; the result is of course a better heating of the water in the boiler, and the lirebox sheets themselves are longer-lived because of this distribution of the flame over a larger area and also because of the sluggishness of the draft, the consequent absence of any gouging effect from the name,

and the elimination of a large area of fire brick from the lower portions of the flrebox sheets thus made permissible. 1t will be further seen that the cloud of fuel projected from the mixing chamber is not one interiorly too rich in fuel and having only about its exterior sufficient additional air for proper combustion, but is one in which surrounded by an envelopv of air sufiicient for its complete combustion 'and the whole cloud of air is permeated and well heated by the thorough mixture within it of the hot air drawn through the flues 34. The lire box is tight and sufficient air for the proper combustion of the fuel admitted is constantly supplied with the fuel through the mixing chamber. Features of great utility result from this method in combination with the length and sluggishness of the flame, one of these advantages is the reduction of the amount of smoke emitted from, the firebox as the result of complete combustion, the oxygen being highly heated in the firebox, and combining perfectly with the carbon in the fuel, thus eliminating the formation of CO; a further advantage lies in the fact that a` locomotive or other heatingl plant equipped with the apparatus of this invention and operating in accordance with its method, does not throw out partly burned cinders the combustion of which is continued on roofs and in elds where such cinders fall setting fire to objects along the railroad right of way or in the locality of the heating plant; whatever hot cinders are emitted from the fire-box are composed of non-combustible, non-volatile .1natter, are rapidly cooled in the outer air, and contain no unconsumed carbon whereby their kindling heat could be maintained after they have dropped to the ground.

Under varying conditions of steam pressure and grade of fuel, it will at times be advisable to reduce the fluid pressure in pipe 44 to lessen the speed with which fluid is ejected from slot 42, and it will also at times be necessary to the most economical practice that a small proportion of air be admitted to the flame through slot 42. For these reasons the rear end of pipe 44 is flared to form a frusto-conical mouth 50 within which is positioned a forwardly tapered steam nozzle 51, the latter being adjustable by any suitable means (not shown) so that it may be moved axially of mouth 50 to increase or decrease the amount of air entering pipes 44 and 43 Aby the injector effect of the steam from the nozzle; or the nozzle 51 may be inserted until it, contacts with the smaller end of mouth 50, so that the ingress or air is prevented and pure steam projected in a sheet from slot 42 instead of a mixture of steam and air.

I claim:

1. The herein described method of burning comminuted fuel, which consists in causing a flame from said fuel to travel the length of a fire-box four times between its introduction and emission.

2. The herein described method of burning comminuted fuel, which consists in causing the flame from said fuel to travel the.

length. of a fire-box four times between its introduction and emission, and spreading said fiame transversely throughout the firebox.

3. The herein described method of burning comminuted fuel, which consists in projecting the flame from a combustible mixture of said fuel backwardly from the lower portion of a fire-box, deflecting upwardly and forwardly from the back of the re-box the flame from said fuel, projecting said flame subsequently against the front wall of the fire-box and spreading it against the side thereof, then deflecting the flame a second time backwardly and upwardly against the back and crown sheets of the lire-box, and then causing` said flame to travel forwardly beneath the crown sheet of the firebox.

4. The v'herein described method of burning comminuted fuel, which consists in projecting the ame from a combustible mixture of said fuel backwardly from the lower forward portion of a fire-box, deflecting upwardly and forwardly from the back of the fire-box the flame from said fuel, projecting said fiame subsequently horizontally against the front wall of the fire-box and spreading it against the side sheets thereof, then deecting the flame a second time backwardly and upwardly against the baclr and crown sheets of the fire-box and then causing said flame to travel forwardly beneath the crown sheet of the fire-box.

5. The herein described method of burning comminuted fuel, which consists in projecting downwardly into the top of a mixing chamber a rich mixture of fuel and air, projecting oppositely into the bottom of said chamber a current of heated air greater in transverse extent than the said rich mixture whereby the rich mixture is enveloped by the heated air, and igniting the mixture thus produced.

6. The herein described method of burning comminuted fuel, which consists in introducing downwardly into the top of a mixing chamber a rich mixture of fuel and air, projecting oppositely and upwardly into said chamber a current of heated' air, projecting horizontally across said first named current a draft of cold air, and igniting the mixture thus produced.

7. The herein described method of burning comminuted fuel, which consists in projecting into a mixing chamber a non-explosive rich mixture of fuel and air in a current having a given transverse dimension, projecting a draft of cold air against said current at right angles thereto and in a volume having its transverse dimension substantially the same as that of said current, causing said draft of air to inject into the mixture thus produced a current of hot air having its transverse dimension greater than that of said rich mixture and igniting the mixture thus produced.

JOSEPH H. COOPER. 

